The Chicago Transit Authority briefly diverted Red Line trains to elevated tracks Sunday night due reports of smoke in the subway tunnel downtown.
Trains were rerouted between Fullerton and Cermak stations due to “fire department activity at Monroe,” the CTA said in a tweet.
CTA spokesman Brian Steele said it happened near a southbound train.
There was no apparent smoke or flame, which would indicate it was a problem with the train’s brakes, Steele said. No one was reported injured.
Trains resumed normal operation within about 30 minutes of the initial report of smoke, CTA said.
